Running the Osaka Loop is all about driving ability, which makes the Civic a perfect machine for the job. Since it is important to maintain maneuverability and nimbleness, you won’t find very many Civics that are over-powered. Popping the hood of one of these Hondas will more than likely reveal a highly-responsive B16A engine, or its larger displacement brethren, the B18C. Rarely will you ever see a K-series engine swap and the B-series engines being used do not even have major modifications to them. Since this is such a high-risk hobby, the possibility of ruining the car or losing it is always a factor so it just makes sense to keep the modifications minimal. It is also traditional to keep the motors lightly-modded because the old Civic one-make circuit races of old were often relegated to having basic mods or no mods at all.